Hoisting accessory

ABSTRACT

An apparatus for use in hoisting heavy loads onto floors within an erected frame of a building by a lift line incorporates an elongated frame mounted for longitudinal movement on a trolley and having a counterweight attached to one end portion thereof and a load supporting arrangement to the opposite end portion. The lift line is secured to the trolley, which is selectively positioned longitudinally along the elongated frame to balance the frame, the counterweight and the load, thereby to facilitate lifting of the load to a desired height. Once the load has been lifted, the frame may be laterally moved to position the load over a receiving surface, and then the position of the trolley may be adjusted along the frame to obtain a desired imbalance between the load and the counterweight for tilting the frame from a horizontal disposition to manipulate the load around ledges and the like and to facilitate the removal of the load from the load supporting device and onto the receiving surface.

[ 1 Oct. 2, 1973 1 1 HOISTING ACCESSORY [76] Inventor: Kolbjorn Saether, 221 N. LaSalle St., Chicago, Ill.

22 Filed: June 21,1971

211 App1.No.: 154,823

[52] 11.8. C1. 294/67 AA, 294/67 R, 294/78 A [51] Int. Cl. B66c 1/00 [58] Field of Search 294/67 R, 67 A, 67 AA, 294/67 C; 212/48, 49; 214/] R, 1 H, 77 R, 78,

[56] References Cited UNITED STATES PATENTS 2,246,142 6/1941 Moore 294/67 AA Primary Examiner-Evon C. Blunk Assistant Examiner.lohnny D. Cherry Att0rneyCarlton Hill et a1.

[57] ABSTRACT An apparatus for use in hoisting heavy loads onto floors within an erected frame of a building by a lift line incorporates an elongated frame mounted for longitudinal movement on a trolley and having a counterweight attached to one end portion thereof and a load supporting arrangement to the opposite end portion. The lift line is secured to the trolley, which is selectively positioned longitudinally along the elongated frame to balance the frame, the counterweight and the load, thereby to facilitate lifting of the load to a desired height. Once the load has been lifted, the frame may be laterally moved to position the load over a receiving surface, and then the position of the trolley may be adjusted along the frame to obtain a desired imbalance between the load and the counterweight for tilting the frame from a horizontal disposition to manipulate the load around ledges and the like and to facilitate the removal of the load from the load supporting device and onto the receiving surface.

25 Claims, 14 Drawing Figures 3,596,968 8/1971 Holm 294/67 AA 3,244,446 4/1966 Bopp 294/67 AA 3,177,027 4/1965 Paul et a1. 294/67 A 3,341,243 9/1967 Archer 294/67 R 3,521,924 7/1970 Wallenius 294/67 R FOREIGN PATENTS OR APPLICATIONS 1,480,384 5/1967 France 294/67 R mum-n.

HOISTING ACCESSORY BACKGROUND OF THE INVENTION The present invention generally relates to hoisting accessories and more particularly refers to an apparatus including a counterweight for use in lifting loads with a lift line and maneuvering the load ontoa floor within a frame of a building being erected.

In lifting loads onto floors of buildings under construction, considerable effort has been required heretofore to pull the load suspended at the end of a lift line or cable into the building frame and over a receiving surface, since it was necessary to deflect the heavy lift cable for swinging the load into a position overlying one of the floors of the building.

SUMMARY OF THE INVENTION A hoisting apparatus for use in lifting heavy loads onto floors within an erected frame of a building com.- prises an elongated frame or beam structure movable longitudinally on a trolley to which a lift cable or line is attached. The elongated beam has a counterweight suspended from one end portion thereof and a load supporting arrangement disposed at the opposite end portion for suspending a load, such as a pallet or bundle of building materials, from the beam. With the counterweight and the load supporting arrangement suspended from the beam, a center of gravity of the loaded beam is located a certain distance below the connection of the lift cable to the trolley, and thus, when the trolley is positioned in vertical alignment with the center of gravity of the apparatus, the elongated beam is balanced in a stable, horizontal disposition.

With the trolley positioned to balance the apparatt s, the load is horizontally spaced from the lift cable, thereby enabling the load to be laterally moved, once it is lifted to a desired height, for positioning the load over a load receiving surface, such as a floor in the frame of a building being erected without requiring the lift cable to be deflected. I

To gently lower the load onto the receiving surface without operating a crane motor controlling the lift cable, the position of the trolley along the beam is adjusted to an imbalanced position selected for tilting the beam from the horizontal position in a direction to lower the load supporting end of the beam. Also, the beam may be tilted from the horizontal to maneuver the load over a ledge, windowsill or the like and under an overhang or other obstruction on the erected build.- ing frame. The lift cable is connected to the trolley in a manner to form a pivotal connection enabling relative pivotal movement between the lift cable andthe trolley about an axis extending transversely of the beam, thereby to facilitate the tilting of the beam.

The adjustment of the trolley along the beam may be by gravitational forces or by power means, such as an electric motor. With either type of system, the proper position of the trolley along the beam is assured by stopping the trolley at the proper location and holding the trolley in that selected location by an appropriate holding means. In the powered embodiment, theholding means comprise a brake associated with the motor and normally preventing movement of the trolley along the beam and releasing to permit movement whenever the motor is energized. One form of braking means for the non-powered embodiment comprise a closed hydraulic system having a piston reciprocally disposed .in

a bore of a cylinder with the piston operatively connected to the trolley. Thus, by controlling the flow of fluid from one end of the cylinder to the other, the movement of the trolley may be controlled, and when fluid flow-between the opposite ends of the cylinder is prevented, the trolley is locked or held in a certain position along the beam.

The ability of the beam to tilt about its connection to the lift line or cable enables the beam to be manually tilted for gravitationally moving the trolley along the beam during loading, unloading or balancing operations. Thus, it is possible to move the trolley forward along the beam toward the load supporting arrangement to pickup a load by manually tilting the beam slightly upward toward the load during a loading operation, and during an unloading operation, the load supporting end of the beam may be tilted slightly downward to move the trolley rearwardly on the beam for lowering the load onto a load receiving surface.

If desired, stay lines, including a shock cord section, may be attached to the opposite ends of the beam and secured to the lift line thereby permitting limited tilting movement of the beam while preventing violent swinging of the beam in the event the counterweight or load should slip.

The hoisting apparatus may be adapted to handle various types of loads, such as pallets, prefabricated units and the like by utilizing interchangeable load supporting devices. The load supporting devices may in- BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a reduced elevational view illustrating the hoisting apparatus of the present invention, including a fork lift carrier for the load;

I FIG. 2 is a reduced elevational view illustrating the hoisting apparatus of the present invention equipped with a holding plate for supporting the load;

FIG. 3 is a reduced elevational view of the hoisting apparatus of the present invention including a holding bar from which a load may be suspended;

FIG. 4 is a reduced elevational view illustrating the hoisting apparatus equipped with aholding plate for carrying a load and shows the manner in which the apparatus may be tilted to maneuver the load over an upstanding ledge;

FIG. Sis a reduced elevational view illustrating the hoisting apparatus of the present invention including a holding plate for supporting a load and shows the manner in which the device may be tilted to maneuver the load under a depending ledge;

FIG. 6 is a fragmentalside elevational view of one embodiment of the hoisting apparatus of the present invention, including powered means for moving the trolley longitudinally along the elongated beam or frame of the apparatus, and shows a control arm for the apparatusin a horizontal, operative position;

FIG. 7 is a front end view of the apparatus illustrated in FIG. 6 with the control arm shown in a vertical position;

FIG. 8 is a cross sectional view taken substantially alongline VIIIVIII of FIG. 6;

FIG. 9 is a rear end view of the apparatus shown in FIG. 6;

FIG. is a fragmental side elevationalview of an alternative embodiment of the apparatus of the present invention, including a hydraulic braking system for maintaining the trolley at a selected position along the elongated frame or beam, and shows a control arm in a horizontal, operative position;

FIG. 11 is a front end view of the apparatus of FIG. 10 with the control arm in a vertical position;

FIG. 12 is a sectional view taken substantially along line XIIXII of FIG. 11;-

FIG. 13 is a schematic view illustrating an electrical control circuit utilized to control the apparatus illustrated in detail in FIGS. 6 through 9, inclusive;

FIG. 14 is a schematic view of a hydraulic circuit utilized to control the hydraulic braking system of the embodiment illustrated in FIGS. 10 through 12, inclusive.

DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS Referring to the drawings, a hoisting apparatus 10 for use in lifting heavy loads onto floors within the erected frame of a building or onto shelves in a warehouse generally comprises an elongated frame or beam structure 11 having a counterweight 12 attached at one end portion thereof and a load supporting arrangement 13 attached at an opposite end portion thereof. A lift line or cable 14 for lifting the apparatus 10 to a desired height is secured to a trolley 15 mounted on the frame 11 for movement longitudinally therealong between the load supporting arrangement 13 and the counterweight 12.

In the embodiment illustrated in the drawings, the counterweight 12 and the load supporting arrangement 13 are both suspended from the elongated frame or beam 11. In that manner, a center of gravity of the loaded beam is located a certain distance below the beam for enabling the lift line 14 to be connected to the trolley at a point closely adjacent to and slightly spaced above the beam 11, thereby resulting in a stabilizing arm" having a length equal to the distance between the connection of the lift line to the trolley 15 and the center of gravity of the loaded apparatus.

Accordingly, when the trolley 15 is longitudinally adjusted along the beam to a position selected to be in vertical alignment with the center of gravity of the apparatus 10, the apparatus is supported in a stable, balanced condition with the beam being disposed substantially horizontally. The adjustment of the trolley 15 to a position on either side of the balanced position causes the beam to assume a disposition tilted from the horizontal in a direction dependent upon the position of the trolley. On the other hand, by tilting the beam 11, the trolley 15 will ride along the beam in an uphill direction.

To prevent undesird movement of the trolley 15 along the beam 11, the presentinvention contemplates providing holding means for normally retaining the trolley at a selected position along the beam and for enabling selective movement or adjustment of the trolley along the beam, as desired.

Also, if desired, the apparatus 10 may include safety lines or stays 16, 16 extending from the lift line 14 to the opposite. end portions of the frame or beam 11. A pair of eye bolts l7, 17 secured, by appropriate means, such as welding, to the opposite end portions of the elongated frame or beam 11 form convenient means for attaching the safety lines or stays to the apparatus 10. To take up excess slack, each of the safety lines 16,

16 includes a section of shock cord 18, shown in FIGS. 1 through 3, inclusive, by a dashed line. An adjustable clamp, as at 19, may secure one or both of the safety lines l6, 16 to the frame, as illustrated in FIGS. 2 and 4, thereby to facilitate the adjustment of the length of the stays for various load positions.

In accordance with the principles of the present invention, the use of the hoisting apparatus 10 with loads of various configurations is facilitated by interchangeable load supporting arrangements adapted to handle bundles of material, pallets, prefabricated units and the like. As illustrated in FIG. 1, the load supporting arrangement 13 may be in the form ofa fork for use with a pallet or crate. The load supporting arrangement may take the form of a solid holding or support plate 130 on which a stack or bundle of material may be positioned, as illustrated in FIG. 2. Also, a sling 21 may be attached to a holding bar 13b, as shown in FIG. 3, or a bundle or a prefabricated unit may be strapped or otherwise secured to a holding bar or plate 130 extending at right angles to the frame 11, as illustrated in FIGS. 4 and 5.

In operation, the unloaded apparatus 10, suspended at the end of the lift line 14 and having the trolley 15 selectively positioned at an unloaded, balanced position, is moved adjacent to a load to be hoisted. To load the apparatus 10, the trolley position is adjusted rearwardly along the beam 11 toward the counterweight to tilt the beam in a direction for lowering the load supporting arrangement 13 to a pickup position. Once the load has been secured, the apparatus 10 is balanced by moving the trolley 15 forwardly towardthe load and stopping the trolley at a position selected to balance the beam 1 l on the trolley in a generally horizontal disposition. The balanced, loaded apparatus 10 may then be hoisted to a desired height.

As illustrated in FIG. 1, with the apparatus 10 balanced at the end of the lift line 14, the load is carried at the end of a cantilevered beam, thereby enabling the load to be moved over a load receiving surface, such as a floor, within an erected frame of a building or the like without requiring the lift line to be deflected. Also, the load carried at the end of the cantilevered beam may be maneuvered inwardly of an upstanding ledge, such as the ledge 22, as illustrated in FIG. 2, and then lowered toward the floor or other load receiving surface. On the other hand, a loadmay be loaded onto the apparatus 10 from the floor at a position inwardly of the ledge 22 and then hoisted over the ledge and outwardly of the building.

In accordance with the principles of the present invention, as illustrated in FIG. 3, to gently case a load onto the floor or other load receiving surface, from a position a few inches above the floor, the trolley 15 is adjusted rearwardly along the beam 11 so that the beam tilts toward the floor. The movement of the trolley 15 along the beam 11 may be controlled by an unloading crew working on the floor where the load is to be unloaded. In that manner, the last critical few inches of the unloading maneuver is accomplished without requiring the operation of the crane controlling the lift line 14.

. If required, the beam 11 may be tilted from a horizontal disposition before the beam moves endwise into the frame of an erected building, thereby enabling the load to be maneuvered around upstanding ledges, such as the ledge 23, as illustrated in FIG. 4 or under overhanging portions, such as the overhanging beam 24, as illustrated in FIG. 5.

Referring now to FIGS. 6 through 9, inclusive, for a detailed description of one embodiment of the hoisting apparatus 10, the beam 11 comprises an I-beam having a medial web portion 26 and a pair of transverse flanges 27 and 28. The upper flange 27 forms a pair ofdownwardly projecting rails 29 and 30 extending transversely outwardly on opposite sides of the medial web 26, thereby to provide track means in the form of rail surfaces on opposite sides of the beam on which wheels 31 of the trolley ride. An inverted channel 32 extending longitudinally along the beam flange 27 and has a pair of depending flanges 33, 33 welded or otherwise secured to the flange in a manner to reinforce the rails 29 and 30 and form a raceway.

The trolley 15 has a body characterized by a pair of upwardly converging sidewalls 34, 34 joined by a pin 36 disposed transversely of the beam 1 1. A pair of hubs 37, 37 attached respectively to opposite ones of the trolley sidewalls 34, 34 have aligned through bores 38 sized to closely receive the pin 36. The hubs 37 are attached to their associated trolley sidewall 34 by appropriate means, such as the rivets 39, and cotter pins as at 41 or other appropriate means retain the pin 36 within the hubs.

In accordance with the present invention, the lift line 14 is attached to the trolley 15 in a manner to enable pivotal movement between the line attachment means and the lift line. The means for attaching the lift line to the trolley include a closed ring 42 disposed between the pair of hubs 37, 37 and having the pin 36 passing through an open center of the ring, thereby to permit relative pivotal movement between the ring 42 and the pin 36 secured to the trolley. One or more washers as at 43 may be interposed between opposite sides of the ring 42 and the inner ends 44 of the hubs 37 to enhance relative pivotal movement.

A pair of the wheels 31 are disposed on either side of the beam 11 and ride on the rails 29 and 30, thereby to prevent relative tilting movement between the trolley 15 and the beam 11 so that the tilt axis of the beam is at the line attachment point. Each of the wheels 31 is journaled on a stub shaft 46 which in turn is secured to the associated trolley sidewall 34 and extends perpendicularly thereto. The angle of inclination of the upwardly converging sidewalls 34 is selected so that the sidewalls extend substantially perpendicularly to the inclined, downwardly projecting rail surfaces 29 and 30, and thus, the wheels 31 are disposed at an appropriate angle to properly engage the inclined rail surfaces. The stub shafts 46 are positioned relative to the connecting pin 36 so that the axis about which the beam may tilt is closely adjacent to and slightly spaced above the beam 11.

The counterweight 12 is suspended from the beam 1 l and secured to a fox frame 49 having a pair of parallel, spaced apart sidewalls 51, 51, a top wall 52 and a bottom wall 53. The top wall 52 of the frame 49 is adjustably secured to the lower beam flange 28, so that the drive mechanism may be selectively tightened, and the counterweight 12, which may include a concrete block is secured by appropriate means, such as the nut and bolt assemblies 54 to the frame bottom wall 53. In that manner, the counterweight is suspended beneath the beam so that a center of gravity of the apparatus 10 is located below the beam, and thus below the pivotal attachment between the lift line and the trolley.

It is contemplated by the present invention to provide interchangeable load supporting devices and means secured to an end of the beam 11 opposite the counterweight 12 for attaching one of the interchangeable devices to the beam. As illustrated in FIGS. 6 and 7, means for attaching one of the interchangeable load supporting devices comprise a depending arm 57, consisting of an I-beam, and having an upper end portion 58 welded or otherwise secured to the I-beam 11. At a lower distal end 59 of the arm 57, a cross beam 61 is secured to the arm and extends transversely of the beam 11 an equal distance on opposite sides thereof. A plate 62 secured to the upper flange 27 extends longitudinally outwardly of the forward end of the beam 11, thereby to form a support platform for vertically supporting one of the interchangeable attachment means.

One form the interchangeable supporting means, as illustrated in FIGS. 6 and 7, includes a fork lift device having a pair of outwardly tapered arms 63, 63 spaced apart a distance to be received in appropriate apertures formed in a standard pallet. The arms 63, 63 are secured to a lower frame member 64 of a generally rectangular frame 66. The frame 66 also includes a pair of side members 67 and an upper frame member 68. To attach the fork lift device to the beam 11, a bottom wall 68a of the upper frame member 68 is supported on the attachment plate 62 at a position so that the lower frame member 64 engages the transverse beam 61 of the attachment means. The fork lift device is retained in position by a plurality of nut and bolt assemblies as at 69 passing through aligned apertures formed in the support plate 62 and a flange 71 extending outwardly of the upper frame member 68. An upturned ledge 72 at the outer end of the plate 62 abuts the end of the flange 71 to prevent inadvertent forward movement of the fork lift, or other interchangeable supporting device. Inadvertent upward movement of the fork lift device 66 is prevented by a plate 73 extending parallel to the plate 62 and spaced a distance therebeneath selected so that the plate closely overlies the lower frame member 64 of the fork lift device.

As illustrated in FIGS. 2 through 5, other forms of supporting devices may be attached to the beam 11, with each of those devices including a rectangular frame similar to the frame 66 of the fork lift device. Also, other positions of the illustrated supporting devices are possible.

In accordance with one embodiment of the present invention, as illustrated in FIGS. 6 through 9, inclusive, the movement of the trolley 15 along the beam 11 is by powered means with braking or holding means normally retaining the trolley at a selected position and releasing to permit movement of the trolley whenever the powered means are operated.

The powered means comprise a reversible electric motor 81 driving a pair of sprockets 82, 82 via a worm gear arrangement 83. The motor 81 is mounted within the box frame 49 and secured to the top wall 52 thereof. The sprockets 82, 82 disposed respectively on opposite sides of the beam 11, rotate a shaft 84 journaled in appropriate bearing blocks 86, 86 secured to the beam 11 so that the shaft extends transversely of the beam and outwardly on opposite sides thereof. A pair of sprockets 87, 87 eorotatably carried on the shaft 84 in alignment with the sprockets 82, 82 are driven via a pair of chains 88, 88.

In order to transfer the rotation of the shaft 84 to the movement of the trolley 15 along the beam 11, a pair of chain lengths 89, 89 disposed respectively on opposite sides of the beam 11, each have opposite end portions 91 an 92 thereof anchored to opposite ends of the trolley 15. Each of the chains 89 is trained around a pair of sprockets 93 and 94 disposed respectively at the forward and rear ends of the beam 11. The sprockets 93, at the forward end of the beam 11, are corotatably attached to a shaft 96 having its opposite end portions journaled in appropriate bearing means 97 secured on opposite sides of the beam 11. The driving sprockets 94 are corotatably attached to the driven shaft 84. Thus, rotation of the shaft 84 moves the opposite ends of the chain 91 and 92, and thus, the trolley 15, longitudinally along the beam 11 to adjust the position of the trolley.

In order to retain the trolley 15 at a selected position along the beam 11, the reversible electric motor 81 includes a brake, indicated generally by reference numeral 99, engaging an output shaft of the electric motor. The brake 99 normally prevents rotation of the motor output shaft, and thus, prevents rotation of the shaft 84, and releases to permit rotation of the output shaft of the motor whenever the motor is energized to move the trolley along the beam. Since the brake is normally energized, an unexpected interruption in current being supplied to the motor will cause the brake to engage for preventing further movement of the trolley, thereby to provide a fail safe system.

Referring now to FIG. 13, wherein is illustrated a schematic of an electrical circuit for controlling the operation of the motor 83, electrical current is supplied to the circuit 101 via leads 102, 103 and from the circuit to the motor via a common lead 104, a lead 106 to the forward starting winding and a lead 107 to the reverse starting winding. A first series circuit including a normally opened push button switch 108, a forward motor coil 109 and a normally closed, forward limit switch 111 provides current to the forward motor starters 112 whenever the normally opened push button switch 108 is closed, thereby to move the trolley forwardiy along the beam. In a like manner, a second series circuit in parallel with the first series circuitand including a normally opened push button switch 113, a reverse motor coil 1 14 and a normally opened reverse limit switch 116 controls the passage of current to the reverse motor starters 117 to operate the motor in a reverse direction whenever the switch 113 is closed. The forward and reverse limit switches 111 and 116, respectively, are disposed on opposite .ends of the beam 11. Each of the limit switches 111 and 116 consists of a proximity switch which opens when the trolley 15 moves adjacent thereto.

The convenient operation of the push button control switches 108 and 113 is afforded by a control arm 121 having a switch box 122 with the switches 108 and 111 mounted therein, as illustrated in FIGS. 6 and 7. The control arm 121 comprises an inverted channel member pivotally attached as at 124 for pivoting movement between a generally horizontal, operative position, as shown in FIG. 6, and a generally vertical position, as illustrated in FIG. 7. The control arm 121 is maintained in the operative position by one of the nut and bolt assemblies 69 which passes through an aperture 126 formed in the control arm to be in alignment with the apertures in the support plate 62 and the flange 71 when the control arm is in the horizontal position. Certain load configurations may require that the control arm 121 by pivoted to the vertical position so that the load, such as concrete panels, may be properly secured to the forward end of the beam 1 1. When in the operative position, the control arm 121 provides a convenient manually engageable portion for use in maneuvering the beam and for controlling the operation of the powered means for adjustably moving the trolley 15 along the beam.

It is also contemplated by the present invention, as illustrated in FIGS. 10 through 12, inclusive, and 14, to adjust the position of the trolley along the elongated frame or beam by gravitational forces without the assistance of powered means. With the exception of the powered means for moving the trolley along the beam and holding means for retaining the trolley at a selected position, this embodiment is substantially identical to that described hereinabove, and thus, like elements are identified with the same reference numerals to which a prime has been added.

Means for retaining or holding the trolley 15 at a selected position longitudinally along the beam 11' generally comprise a closed hydraulic circuit 131 containing a hydraulic fluid and characterized by an elongated hollow cylinder 132 having a piston 133 received within a hollow interior 134 of the cylinder for slidable movement axially therewithin. A pair of cables 136 and 137 interconnect opposite ends 138 and 139, respectively, of the trolley 15' to opposite ends 141 and 142, respectively, of the piston 133. The cable 136 is trained around a freely rotatable sheave 143 mounted for rotation about an axis extending substantially transversely of the beam 1 1 at a rear end thereof, and in a like manner the cable 137 is trained around a freely rotatable sheave 144 mounted at the forward end of the beam. The cables 136 and 137 enter the opposite ends of the elongated hollow cylinder 132 through appropriate seals as at 145, 145.

With the cylinder 132 filled with hydraulic fluid, movement of the piston 133 within the cylinder is controlled by controlling the flow of hydraulic fluid from one end of the cylinder to the other. The circuit means 131 for controlling the flow of fluid between the ends of the cylinder 132, as illustrated in FIGS. 10, 11 and 14, comprise a four way control valve 146 mounted conveniently for manual operation adjacent to the ban dle 123' on the control arm 121', in fluid communication with a forward end 147 of the cylinder via a fluid line 148 and a flow restrictor 149 and in fluid communication with therear end 151 of the cylinder via a flow line 152 and a fluid restrictor 153. The fluid control valve 146 has a first station 154, a second station 156 and a third station 157. With the first station 154 positioned in fluid communication with the cylinder 132, the hydraulic fluid may flow from the forward end 147 of the cylinder, through a one-way check valve 158 and to the rear end of the cylinder, thereby to permit movement of the trolley rearwardly along the beam. In a like manner, with the third station 157 positioned in fluid communication with the ends of the cylinder, the trolley may be moved only forwardly along the beam. The trolley is retained or held in position along the beam 11 when the second station 156 is positioned in fluid communication with the ends of the cylinder, since that station prevents fluid flow from one end of the cylinder to the opposite end. Accordingly, the position of the fluid control valve 146 controls the movement of the trolley along the beam 11'.

In operation, when movement of the trolley 15 along the beam 11 is desired, the fluid control valve 146 is positioned at either station 154 or 157, depending upon the direction of movement desired, and then the beam is tilted from the horizontal disposition to gravitationally move the beam relative to the trolley. I

As illustrated in FIG. 12, the cables 136 and 137 are attached to a spacer 161 carried on the pin 36' between the hubs 37', 37. In order to clear the hydraulic cylinder 132 which extends above the beam 11, a pair of upwardly converging side straps 162, 162 are fitted over the ends of the pin 36' outwardly of the trolley sidewalls 34' to provide a pivotal connection about which the apparatus may tilt. An inverted U shaped strap 163 joins the upper ends 164 of the side straps 162 and forms a hook, loop or eye onto which the lift line 14 may be secured.

From the foregoing description, it should be noted that the present invention provides a hoisting apparatus comprising an elongated frame or beam movable longitudinally on a trolley to which a lift line or cable is attached. The attachment of the lift line to the trolley is such that the beam may be tilted about a pivot axis closely adjacent to and slightly spaced above the beam for facilitating the loading and unloading operations of the beam and for enabling the beam to be maneuvered around obstructions. Also, by suspending the counterweight and the load underneath the beam, the center of gravity of the apparatus is located below the beam and below the pivotal connection of the lift'line to the beam. In that manner, when the trolley is disposed in vertical alignment, with the combined center of gravity of the loaded apparatus spaced below the beam, the spacing between the lift line connection and the center of gravity provide a moment arm retarding undesired tilting so that the apparatus may be lifted in a stable, balanced condition.

Although those versed in the art may suggest various minor modifications, it should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.

I claim:

1. An apparatus for hoisting loads with a lift line, the apparatus comprising:

an elongated frame;

counterweight means attached to said frame at one end portion thereof;

load supporting means attached to said frame at an opposite end portion thereof;

line attachment means for attaching a lift line to said frame and being adjustably movable along said frame between said load supportingmeans and said counterweight means;

holding means retaining said line attachment means at a selected position along said frame;

powered means for selectively moving said line attachment means longitudinally along said elongated frame and comprising at least one pair of sprockets with one sprocket of the pair beingjournaled at one end portion of said elongated frame and the other of the sprockets journaled at the opposite end portion of the frame;

a length of chain having opposite ends thereof anchored respectively to opposite ends of said line attachment means and being trained around said pair of sprockets; and

reversible motor means selectively driving one of the pair of said sprockets to position said line attachment means at a selected position along said frame; whereby said line attachment means may be positioned selectively along said frame to balance a load and said counterweight to facilitate lifting the load and-when lifted to a desired height said line attachment means may be adjusted to an unbalanced position to assist in the removal of the load from said load supporting means.

2. Apparatus according to claim 1, including means for controlling operation of said motor means and comprising manually actuated means operatively connected with said motor means and mounted conveniently accessible on said frame adjacent to said load supporting means.

3. Apparatus according to claim 1, including means supporting said motor means under said end portion of said frame, and means supporting said counterweight below said motor means.

4; Apparatus according to claim 1, said load supporting means comprising a frame attached to and depending from said opposite end portion of said frame, and interchangeable load engaging means detachably secured to said load supporting frame.

5. The apparatus of claim 1,

said powered means comprising a worm gear transmission driven by said motor means and drivingly connected to said driven sprocket.

6. The apparatus of claim 1,

said holding means comprising a brake normally preventing movement of said driven sprocket and releasing to enable movement of said driven sprocket whenever said motor means is operated.

7. The apparatus of claim 1, comprising control means for controlling the operation of said motor means and comprising manually actuated switch means operatively connected to said motor means;

a control arm attached to said frame adjacent said load supporting means, said switch means being mounted on said control arm.

8. An apparatus for hoisting loads with a lift line, the apparatus comprising:

an elongated frame;

counterweight means attached to said frame at one end portion thereof;

load supporting means attached to said frame at an opposite end portion thereof;

line attachment means for attaching a-lift line to said frame and being adjustably movable along said frame between said load supporting means and said counterweight means;

holding means retaining said line attachment means at a selected position along said frame;

said holding means comprising a closed hydraulic circuit containing a hydraulic fluid;

said circuit including an elongated hollow cylinder carried on said frame and having an interior cylindrical wall;

a piston received in said cylinder for slidable movement axially therewithin;

hydraulic control means controlling the flow of the hydraulic fluid through said circuit to control the movement of said piston within said cylinder;

a pair of sheaves, with respective ones of said sheaves of the pair being journaled at opposite end portions of said elongated frame; and

cable means trained around said sheaves and connecting opposite ends of said piston to opposite ends of said attachment means so that said piston slides axially within said cylinder with movement of said line attachment means along said frame; whereby said line attachment means may be positioned selectively along said frame to balance a load and said counterweight to facilitate lifting the load and when lifted to a desired height said line attachment means may be adjusted to an unbalanced position to assist in the removal of the load from said load supporting means.

9. Apparatus according to claim 8, said hydraulic control means comprising a hydraulic valve mounted adjacent to said opposite end portion of said frame, and including means mounting the valve for convenient manual operationv 10. Apparatus according to claim 9, including a control arm pivotally mounted at one end to said frame at said opposite end portion thereof, and a handle at the opposite end of said arm, said valve being mounted ad'- jacent to said handle.

1 1. An apparatus for hoisting loads with a lift line, the apparatus comprising:

an elongated frame;

counterweight means attached to said frame at one end portion thereof;

load supporting means attached to said frame at an opposite end portion thereof;

line attachment means for attaching a lift line to said frame and being adjustably movable along said frame between said load supporting means and said counterweight means;

holding means retaining said line attachment means at a selected position along said frame;

a manually engageable control arm pivotally attached at one end to said frame adjacent to said load supporting means and having manipulating means at its opposite end; and

means mounted on said arm adjacent to said opposite end for controlling said holding means;

whereby said line attachment means may be positioned selectively along said frame to balance a load and said counterweight to facilitate lifting the load and when lifted to a desired height said line attachment means may be adjusted to an unbalanced position to assist in the removal of the load from said load supporting means.

12. Apparatus according to claim 11, said control arm being'pivotally movable between a horizontal posi' tion and a vertical position, means retaining said control arm in a selected one of said positions, and said manipulating means comprising a handle attached to said member to enable manual operation of the control arm to control the position of said frame.

13. Apparatus according to claim 11, said holding means including an electrical motor and brake means operatively connected with said line attachment means, and said means for controlling said holding means comprising electrical switch means mounted adjacent to said opposite end of said control arm.

14. Apparatus according to claim 11, wherein said holding means include a hydraulic circuit, and said means for controlling said holding means include manually operable control valve means.

15. An apparatus for hoisting loads with a lift line:

an elongated frame having track means extending longitudinally therealong;

counterweight means carried by said frame at one end portion thereof;

load supporting means carried by said frame at an opposite end portion thereof;

a trolley engaging and movable along said track means and having means thereon for attachment of a lift line; and means for controlling movement of said trolley along said track means including flexi ble element means attached to said trolley and extending in opposite longitudinal directions therefrom along said frame means and rotary means carried by said end portions of the frame means on which said flexible element means are trained.

16. Apparatus according to claim 15, including a motor carried by said frame and connected with said flexible element means for operating the same to control the position of said trolley along said track.

17. Apparatus according to claim 15, wherein said trolley is gravitationally movable to different positions along saidtraclc by tilting said frame and permitting the frame to shift gravitationally relative to the trolley, and means for holding said trolley in a selected position along said track by controlling said flexible element means to prevent gravitational shifting of the frame relative to the trolley.

18. In an apparatus for hoisting loads with a lift line:

a single central elongated body beam comprising a longitudinally extending vertical web having an upper edge from which respective opposite laterally extending flanges project along the length of the web providing downwardly facing rails;

counterweight means carried by one end of said beam;

load supporting means carried by an opposite end portion of said beam;

a trolley mounted on said beam and having means in vertical alignment over said web for attaching a lift line to the trolley and having wheels engaging said rails for adjustable movement of the trolley along said beam between said counterweight means and said load supporting means;

holding means for retaining said trolley at a selected position along said beam rails; and

an elongated reinforcing member secured to and along said beam on said flanges.

19. Apparatus according to claim 18, said elongated member comprising an inverted channel having a pair of spaced depending flanges secured to said beam flanges in reinforcing relation to said rails and forming a raceway. v

20. A method of elevating and maneuvering loads with a lift line comprising:

supporting a load at one end of an elongated frame having a counterweight fixed at an opposite end thereof;

attaching a lift line to a trolley engaged movably with rail means extending longitudinally along said frame;

effecting free gravitational longitudinal movement of the frame relative to said trolley comprising tilting the frame in the direction in which it is desired to have the frame move; and

selectively holding the trolley and the frame against relative movement in any adjusted relative position of the trolley and frame.

21. In apparatus for hoisting loads with a lift line, the

apparatus comprising:

an elongated frame comprising a single beam member;

counterweight means attached to said frame at one end portion thereof;

load supporting means attached to said frame at an opposite end portion thereof;

line attachment means for attaching a lift line to said frame and being adjustably movable along said frame between said load supporting means and said counterweight means;

holding means retaining said line attachment means at a select position along said frame, whereby said line attachments means may be positioned selectively along said frame to balance a load and said counterweight to facilitate lifting the load and when lifted to a desired height said line attachment means may be adjusted to an unbalanced position to assist in the removal of the load from said load supporting means;

said load supporting means comprising a single arm rigidly attached to said frame,

interchangeable load engaging means comprising a retangular frame having vertical side bars and horizontal upper and lower bars; and

means detachable securing said load engaging means to upper and lower portions of said load supporting means.

22. In apparatus for hoisting loads with a lift line;

an elongated body beam having track means longitudinally therealong;

counterweight means carried at one end portion of said beam;

load supporting means carried by the opposite end portion of said beam;

21 line attachment trolley engaging said track means for running therealong and having upwardly extending means for attaching a lift line to the trolley;

means carried by said beam and operatively connected wtih said trolley to control movement of the trolley adjustably along said track means;

means carried by said opposite end portion of the beam adjacent to said load supporting means for controlling operation of said means for controlling movement of the trolley for selectively positioning said trolley along said track means to balance a load and said counterweight to facilitate lifting the load and for adjusting said trolley along the track to effect an unbalanced position of the load relative to the counterweight means as desired to assist in maneuvering a load carried by said load supporting mean; and

a handle means carried by and projecting from said opposite end portion of said beam, said means for controlling operations of said means for controlling movement of the trolley being mounted on said handle means.

23. In apparatus fo hoisting loads with a lift line;

an elongated body beam having track means longitudinally therealong;

counterweight means carried at one end portion of said beam;

load supporting means carried by the opposite end portion of said beam;

a line attachment trolley engaging said track means for running therealong and having upwardly extending means for attaching a lift line to the trolley;

means carried by said beam and operatively connected with said trolley to control movement of the trolley adjustably along said track means, said means including flexible element means attached to respective opposite ends of said trolley and rotary means carried by said end portions of said beam over which said flexible element means are trained; and

means carried by said opposite end portion of the beam adjacent to said load supporting means for controlling operation of said means for controlling movement of the trolley for selectively positioning said trolley along said track means to balance a load and said counterweight to facilitate lifting the load and for adjusting said trolley along the track to effect an unbalanced position of the load relative to the counterweight means as desired to assist in maneuvering a load carried by said load supporting means.

24. Apparatus according to claim 23, including a motor carried by one of said beam end portions and operatively connected with the rotary means at the end portion of the beam carrying said motor.

25. Apparatus according to claim 23, including an elongated hollow cylinder mounted longitudinally along said beam, a member reciprocably movable within said cylinder, said flexible element means connected to said reciprocable member and extending beyond the respective opposite ends of said cylinder and over said rotary means, and said means for controlling the position controlling means controlling the position of said reciprocable member in said cylinder and therebycontrolling the position of the trolley through said flexible element means. 

1. An apparatus for hoisting loads with a lift line, the apparatus comprising: an elongated frame; counterweight means attached to said frame at one end portion thereof; load supporting means attached to said frame at an opposite end portion thereof; line attachment means for attaching a lift line to said frame and being adjustably movable along said frame between said load supporting means and said counterweight means; holding means retaining said line attachment means at a selected position along said frame; powered means for selectively moving said line attachment means longitudinally along said elongated frame and comprising at least one pair of sprockets with one sprocket of the pair being journaled at one end portion of said elongated frame and the other of the sprockets journaled at the opposite end portion of the frame; a length of chain having opposite ends thereof anchored respectively to opposite ends of said line attachment means and being trained around said pair of sprockets; and reversible motor means selectively driving one of the pair of said sprockets to position said line attachment means at a selected position along said frame; whereby said line attachment means may be positioned selectively along said frame to balance a load and said counterweight to facilitate lifting the load and when lifted to a desired height said line attachment means may be adjusted to an unbalanced position to assist in the removal of the load from said load supporting means.
 2. Apparatus according to claim 1, including means for controlling operation of said motor means and comprising manually actuated means operatively connected with said motor means and mounted conveniently accessible on said frame adjacent to said load supporting means.
 3. Apparatus according to claim 1, including means supporting said motor means under said end portion of said frame, and means supporting said counterweight below said motor means.
 4. Apparatus according to claim 1, said load supporting means comprising a frame attached to and depending from said opposite end portion of said frame, and interchangeable load engaging means detachably secured to said load supporting frame.
 5. The apparatus of claim 1, said powered means comprising a worm gear transmission driven by said motor means and drivingly connected to said driven sprocket.
 6. The apparatus of claim 1, said holding means comprising a brake normally preventing movement of said driven sprocket and releasing to enable movement of said driven sprocket whenever said motor means is operated.
 7. The apparatus of claim 1, comprising control means for controlling the operation of said motor means and comprising manually actuated switch means operatively connected to said motor means; a control arm attached to said frame adjacent said load supporting means, said switch means being mounted on said control arm.
 8. An apparatus for hoisting loads with a lift line, the apparatus comprising: an elongated frame; counterweight means attached to said frame at one end portion thereof; load supporting means attached to said frame at an opposite end portion thereof; line attachment means for attaching a lift line to said frame and being adjustably movable along said frame between said load supporting means and said counterweight means; holding means retaining said line attachment means at a selected position along said frame; said holding means comprising a closed hydraulic circuit containing a hydraulic fluid; said circuit including an elongated hollow cylinder carried on said frame and having an interior cylindrical wall; a piston received in said cylinder for slidable movement axially therewithin; hydraulic control means controlling the flow of the hydraulic fluid through said circuit to control the movement of said piston within said cylinder; a pair of sheaves, with respective ones of said sheaves of the pair being journaled at opposite end portions of said elongated frame; and cable means trained around said sheaves and connecting opposite ends of said piston to opposite ends of said attachment means so that said piston slides axially within said cylinder with movement of said line attachment means along said frame; whereby said line attachment means may be positioned selectively along said frame to balance a load and said counterweight to facilitate lifting the load and when lifted to a desired height said line attachment means may be adjusted to an unbalanced position to assist in the removal of the load from said load supporting means.
 9. Apparatus according to claim 8, said hydraulic control means comprising a hydraulic valve mounted adjacent to said opposite end portion of said frame, and including means mounting the valve for convenient manual operation.
 10. Apparatus according to claim 9, including a control arm pivotally mounted at one end to said frame at said opposite end portion thereof, and a handle at the opposite end of said arm, said valve being mounted adjacent to said handle.
 11. An apparatus for hoisting loads with a lift line, the apparatus comprising: an elongated frame; counterweight means attached to said frame at one end portion thereof; load supporting means attached to said frame at an opposite end portion thereof; line attachment means for attaching a lift line to said frame and being adjustably movable along said frame between said load supporting means and said counterweight means; holding means retaining said line attachment means at a selected position along said frame; a manually engageable control arm pivotally attached at one end to said frame adjacent to said load supporting means and having manipulating means at its opposite end; and means mounted on said arm adjacent to said opposite end for controlling said holding means; whereby said line attachment means may be positioned selectively along said frame to balance a load and said counterweight to facilitate lifting the load and when lifted to a desired height said line attachment means may be adjusted to an unbalanced position to assist in the removal of the load from said load supporting means.
 12. Apparatus according to claim 11, said control arm being pivotally movable between a horizontal position and a vertical position, means retaining said control arm in a selected one of said positions, and said manipulating means comprising a handle attached to said member to enable manual operation of the control arm to control the position of said frame.
 13. Apparatus according to claim 11, said holding means including an electrical motor and brake means operatively connected with said line attachment means, and said means for controlling said holding means comprising electrical switch means mounted adjacent to said opposite end of said control arm.
 14. Apparatus according to claim 11, wherein said holding means include a hydraulic circuit, and said means for controlling said holding means include manually operable control valve means.
 15. An apparatus for hoisting loads with a lift line: an elongated frame having track means extending longitudinally therealong; counterweight means carried by said frame at one end portion thereof; load supporting means carried by said frame at an opposite end portion thereof; a trolley engaging and movable along said track means and having means thereon for attachment of a lift line; and means for controlling movement of said trolley along said track means including flexible element means attached to said trolley and extending in opposite longitudinal directions therefrom along said frame means and rotary means carried by said end portions of the frame means on which said flexible element means are trained.
 16. Apparatus according to claim 15, including a motor carried by said frame and connected with said flexible element means for operating the same to control the position of said trolley along said track.
 17. Apparatus according to claim 15, wherein said trolley is gravitationally movable to different positions along said track by tilting said frame and permitting the frame to shift gravitationally relative to the trolley, and means for holding said trolley in a selected position along said track by controlling said flexible element means to prevent gravitational shifting of the frame relative to the trolley.
 18. In an apparatus for hoisting loads with a lift line: a single central elongated body beam comprising a longitudinally extending vertical web having an upper edge from which respective opposite laterally extending flanges project along the length of the web providing downwardly facing rails; counterweight means carried by one end of said beam; load supporting means carried by an opposite end portion of said beam; a trolley mounted on said beam and having means in vertical alignment over said web for attaching a lift line to the trolley and having wheels engaging said rails for adjustable movement of the trolley along said beam between said counterweight means and said load supporting means; holding means for retaining said trolley at a selected position along said beam rails; and an elongated reinforcing member secured to and along said beam on said flanges.
 19. Apparatus according to claim 18, said elongated member comprising an inverted channel having a pair of spaced depending flanges secured to said beam flanges in reinforcing relation to said rails and forming a raceway.
 20. A method of elevating and maneuvering loads with a lift line comprising: supporting a load at one end of an elongated frame having a counterweight fixed at an opposite end thereof; attaching a lift line to a trolley engaged movably with rail means extending longitudinally along said frame; effecting free gravitational longitudinal movement of the frame relative to said trolley comprising tilting the frame in the direction in which it is desired to have the frame move; and selectively holding the trolley and the frame against relative movement in any adjusted relative position of the trolley and frame.
 21. In apparatus for hoisting loads with a lift line, the apparatus comprising: an elongated frame comprising a single beam member; counterweight means attached to said frame at one end portion thereof; load supporting means attached to said frame at an opposite end portion thereof; line attachment means for attaching a lift line to said frame and being adjustably movable along said frame between said load supporting means and said counterweight means; holding means retaining said line attachment means at a select position along said frame, whereby said line attachments means may be positioned selectively along said frame to balance a load and said counterweight to facilitate lifting the load and when lifted to a desired height said line attachment means may be adjusted to an unbalanced position to assist in the removal of the load from said load supporting means; said load supporting means comprising a single arm rigidly attached to said frame, interchangeable load engaging means comprising a retangular frame having vertical side bars and horizontal upper and lower bars; and means detachable securing said load engaging means to upper and lower portions of said load supporting means.
 22. In apparatus for hoisting loads with a lift line; an elongated body beam having track means longitudinally therealong; counterweight means carried at one end portion of said beam; load supporting means carried by the opposite end portion of said beam; a line attachment trolley engaging said track means for running therealong and having upwardly extending means for attaching a lift line to the trolley; means carried by said beam and operatively connected wtih said trolley to control movement of the trolley adjustably along said track means; means carried by said opposite end portion of the beam adjacent to said load supporting means for controlling operation of said means for controlling movement of the trolley for selectively positioning said trolley along said track means to balance a load and said counterweight to facilitate lifting the load and for adjusting said trolley along the track to effect an unbalanced position of the load relative to the counterweight means as desired to asSist in maneuvering a load carried by said load supporting mean; and a handle means carried by and projecting from said opposite end portion of said beam, said means for controlling operations of said means for controlling movement of the trolley being mounted on said handle means.
 23. In apparatus fo hoisting loads with a lift line; an elongated body beam having track means longitudinally therealong; counterweight means carried at one end portion of said beam; load supporting means carried by the opposite end portion of said beam; a line attachment trolley engaging said track means for running therealong and having upwardly extending means for attaching a lift line to the trolley; means carried by said beam and operatively connected with said trolley to control movement of the trolley adjustably along said track means, said means including flexible element means attached to respective opposite ends of said trolley and rotary means carried by said end portions of said beam over which said flexible element means are trained; and means carried by said opposite end portion of the beam adjacent to said load supporting means for controlling operation of said means for controlling movement of the trolley for selectively positioning said trolley along said track means to balance a load and said counterweight to facilitate lifting the load and for adjusting said trolley along the track to effect an unbalanced position of the load relative to the counterweight means as desired to assist in maneuvering a load carried by said load supporting means.
 24. Apparatus according to claim 23, including a motor carried by one of said beam end portions and operatively connected with the rotary means at the end portion of the beam carrying said motor.
 25. Apparatus according to claim 23, including an elongated hollow cylinder mounted longitudinally along said beam, a member reciprocably movable within said cylinder, said flexible element means connected to said reciprocable member and extending beyond the respective opposite ends of said cylinder and over said rotary means, and said means for controlling the position controlling means controlling the position of said reciprocable member in said cylinder and thereby controlling the position of the trolley through said flexible element means. 